|Min OS X: Any Version Requires: Minijack Audio Port
Sound from WithinThe first thing buyers will notice is the volume potential of the headphones. The Sennheiser PC 150 is a loud set. Turning up the inline volume on the headphones takes the sound to surprising levels, completely unexpected for gaming headsets. Sennheiser includes a warning with the headphones admonishing prolonged listening with the volume maxed out, lest one damage his or her ears (probably because of the advertised sound pressure level of 114 dB at 1 KHz and 1 volt RMS).
Any audio junkie knows that it’s not enough to know a pair of speakers or headphones to have good volume potential — they must be able to meet that volume without excessive signal distortion. Clipping is a form of sound distortion that occurs when signal strength exceeds the capability of the speakers or headphones to output sound at that volume, resulting in the addition of a harsh buzzing sound. Prolonged clipping can severely damage a speaker. Much to my surprise, with the Macintosh’s built in sound card and my M-Audio Revolution, maxing out every volume control along the signal path still failed to produce clipping. Even my pair of Sony MDR-7506 studio monitoring headphones would clip at such high volumes. It would require the addition of an amplifier to my audio setup before the Sennheiser PC 150 began clipping.
Even before a pair of headphones or speakers begins to clip, many drivers will begin to lose their equalization. Oftentimes, at high volumes, high-frequency sounds become too harsh, as mids and lows are unable to maintain their volumes relative to the bracing high tones. This problem is ubiquitous on consumer-level speakers and headphones; it would take a large investment of money to find a speaker/headphone and amplifier that maintains quality equalization over a very large volume range.
That said, I was again surprised at the capabilities of the PC 150. At the upper range of its volume potential, the falloff distortion was comparatively minor. The high-end tones, though noticeably hot, were not disturbingly so, as they can be in many non-professional devices.
Even outside of the discussion of volume potential, the quality of the PC 150 shined. Sound reproduction was notable considering the price, matching the quality of most mid-range consumer gaming speaker/subwoofer sets, and certainly exceeding the quality of any computer-integrated speaker system. The headphones reproduced sub-bass tones convincingly, providing a satisfying thumping in my head, although the sub-bass frequencies seemed to lack the comparative sharpness of the middle- and high-frequency tones. In general, however, the sound reproduction capabilities of the PC 150 were above average.
The PC 150 boasts a frequency response between 18 Hz and 22 KHz, certainly better than most headphones of its genre.